Devices of the stated type are employed, in particular, for the production of so-called bored piles, panels, cut-off walls or the like. Initially, a hole is produced in the ground, for example through drilling or cutting. The hole is usually stabilized by means of a stabilizing liquid. Afterwards, the hole is filled up from the bottom with a filling material, for instance plaster, gravel, sand or concrete. In this process, the discharge opening is guided upwards in line with the rising filling level. The stabilizing liquid is displaced upwards and normally led off in a controlled manner.
To fill a hole in the ground various types of filling pipes are known. For example DE 701 932 describes an extensible filling pipe which comprises several pipe parts inserted telescopically into one another, of which the uppermost one has a receiving hopper for concrete and the lowermost one has a pipe mouth.
A filling pipe for introducing underwater concrete is described in DE 1 113 427. This filling pipe comprises a feed hopper and several detachable pipe pieces connected thereto which can each be dismantled into two shells. In the concreting process the filling pipe is pulled upwards. The shells of the uppermost pipe piece are removed sideways so that the following pipe piece can move up.
Another device and a method for introducing a hardening mass underwater is known from DE 1 928 993. In this case, a flexible hose or duct is used as a filling pipe which, by the action of the surrounding water pressure, is compressed so that a uniform outflow of the hardening mass can be realized underwater. The handling of the filling pipes above the hole and the devices required for this prove to be elaborate and complex.